BI SPS incompatible with Portal SPS

Hi All,

I am working in BI integration with portal. I have got the following query.

We have got a BI portal which was running on Ver 7.0 SPS 13 and later upgraded the BI system (and not the portal) to SPS 16. After that some errors started coming up on Portal. Some reports don't come up correctly, export to excel fails etc. Could anyone please tell whether we have to upgrade the portal also?